SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '85218d90ff01cc907b880ca3088932668ad6a723b5714d945fa11383f919d2e2' 
  AND token = 'TqtZfKqj2/0kvKEBW4L+T6Tkr4pHvIRmhrP6MhmLmgA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}